Engine



septv 3, 1935.

A. J. MEYER mmm ENGINE Filed March 5, 1952 2 Sheets-Sheet INVENTOR. flfldre f/Mejger A. J. MEYER epi; 3,, 1935.

ENGINE Filed March 5, 1952 2 Sheets-Sheet 2 INVENTOR. flfldre Mg qr ATTORNEY.

Patented Sept. 3, 1935 straits creme tinental corporation of Virginia,

Motors Corporation, Detroit, Mich, a. 7

Application March 3, 1932, Serial No. 596,414

1 Claim.

My invention relates to internal combustion engines of the sleeve valve type and more particularly to counterbalancing means for opposing the unbalanced rocking couple set up by the sleeve motion in a multi-cylinder in-line engine.

For purposes of illustration I have shown a sleeve valve engine of the Burt-McCollum type wherein a single sleeve per cylinder is moved with a combined reciprocating and oscillating motion in controlling the engine intake and exhaust.

A study of the inertia forces of the sleeve mo tion in a single sleeve valve engine has revealed that these forces can be suitably analyzed into vertical and rotational components. It has been found that in multi-cylinder engines, where the engine timing is spaced at equal time intervals, that the rotational components are in complete balance. However, With regard to the vertical components, a harmonic analysis shows that the unbalanced forces of one cylinder consists of an infinite series of components, each of which Va- H is most important since its maximum is approxiries as a sine wave.

The analysis is given by the following formula:

wherein F is the total unbalanced vertical force;

I is valve shaft angle;

A, B, C, etc., are constants.

It has been further found that the constants (or coefiicients) A and B are the only ones which for practical purposes have to be taken into consideration since all other constants are very small. Therefore, the unbalanced force per cylinder may be closely approximated by F=A cos. +B cos. 2 5

As will be clear to anyone familiar with an analysis of this sort, the shaking force for a multi-- cylinder engine, where the timing of the sleeve comes at equal time intervals, will be zero. However, the unbalanced forces of all cylinders will give rise to a primary and secondary rocking couple acting in the longitudinal plane of the engine containing the cylinder axes which may be represented by the following formulae:

Primary rocking couple (P) :D cos. i +o) Secondary rocking couple, (S) =E cos. (Zea-p) a and ,8 are phase angles and D and E are constants. 7

These rocking couples P and S acting in a Iongitudinal engine plane containing the cylinder axes cause an objectionable vibration and it has been foundthat the primary rocking couple (P) mately ten times greater than the secondary Therefore by proper proportioning, it is thus rocking couple. Therefore, my present invention is concerned principally with eliminating the primary rocking couple which removes the objectionable engine vibration.

It is the object ofmy invention to provide a 5 construction wherein a maximum of balance is obtained by incorporating suitable means associated with the engine valve shaft for opposing v the primary rocking couple which is developed in the engine during the operation thereof.

In order to obtain this result I have preferably provided my engine with two rotating shafts having axes extending substantially parallel to the axis of the crankshaft or to thlongitudinal engine plane containing the cylinder axes, one on each side thereof. These two shafts are preferably located approximately equal distances laterally from the said longitudinal'engine plane although the exact vertical spacing of said shafts with respect to each other is of little or no consequence. Both of these shafts, one of which may be the valve shaft, operate at one-half engine speed but in opposite directions with respect to each other. Each shaft carries a counterweight at the front and rear, which weights are so timed in operation as to be located substantially symmetrical with respect to the longitudinal plane of the engine containing the cylinder axes. It may be noted that if these counterweights are all of equal moment, that the horizontalcomponents of the centrifugal forces induced by the rotation of the counterweights will cancel each other at all times leaving a vertical resultant that varies as the cosine wave.

possible to create a rocking couple of the value P=D cos. (e-l-a) but acting at all times to oppose the primary rocking couple caused by the vertical reciprocation of the sleeve as mentioned 4 above.

For a more detailed understanding of my invention, reference may be had to the accompanying drawings which illustrate one form which my invention may assume, and in which:

Fig. 1 is a vertical transverse sectional View through a typical engine cylinder and showing an engine having, a valve shaft for operating the sleeves and a balance shaft forbalancing the primary rocking couples,

Fig. 2 is a fragmentary elevational View of the engine showing the valve shaft and balance shaft,

Fig. 3 is an end elevation thereof showing the balancing means and the relation of the counterweights carried by said valve shaft and balance shaft and taken substantially on the line 33 of Fig. 2,

Fig. 4 is an end elevational view of the other end of the engine and showing the valve shaft and balance shaft, said figure taken on the line 4- of Fig. 2, and

Fig. 5 is a side elevational view of the balance shaft.

In the accompanying drawings illustrating one embodiment of my invention, it designates the crankcase of a single sleeve valve engine A, said crankcase being provided with a plurality of aligned cylinders M and a plurality of cylinder heads i2, each cooperatively associated with an engine cylinder and each having a portion l3 depending within the cylinder and spaced from the Walls thereof to provide a sleeve pocket l t for accommodating the upper portion of a single sleeve E5. The sleeve valve i5 is constructed for operation within an engine cylinder and is provided with suitable intake and exhaust ports l6 and H adapted for cooperative association with the cylinder intake and exhaust ports l3 and i9 respectively. An engine crankshaft 20 is supported by suitable bearings 2! in the crankcase and is provided with crank portions 22 to which the connecting rods 23 may be connected, these connecting rods each being associated with a piston 24 operating within the sleeve valve E5.

The sleeve valve i5 is operated by any suitable mechanism, and in the illustrated embodiment of my invention I have provided a layshaft, in particular a wobble valve shaf 25 having a plurality of wobble cranks 25, each of these wobble cranks being connected with th respective sleeve valves by means of the connecting links or rms 2?, the outer portion of said arms or links being provided with a ball socket 28 adapted for cooperative engagement with the ball 25 carried by the sleeve valve 55. The wobble valve shaft is provided with intermediate bearing portions 38 and the end bearing portions 3!, these bearing portions adapted for cooperative association with bearings carried by the crankcase, Fig. 1 illustrating one of said bearings 32 which is adapted to support one of the end bearing portions 3! of the valve shaft.

In the present embodiment of my invention the means for counterbalancing the primary rocking couple set up in the engine comprises a balance shaft 35 supported by the engine crankcase and extending parallel to the engine crankshaft and to the other side thereof from the valve shaft 25. counterweights 3G and 37 are carried respectively at the front and rear end of the valve shaft and counterweights 38 and 39 are carried respectively at the front and rear end of the balance shaft 35. The counterweights at the front end of said shafts are preferably arranged symmetrical with respect to the engine longitudinal plane containing the cylinder axes and the counterweights at the rear of said shafts are also preferably arranged symmetrical with respect to the plane containing the cylinder axes but angularly spaced 180 degrees with respect to the counterweights at the front end of the shafts. More particularly the counterweights 35 and 31 carried by the valve shaft 25 are angularly spaced 180 degrees and the counterweights 38 and 39 carried by the balance shaft 35 are angularly spaced 180 degrees. (See Figs. 3 and i.)

It may be noted that the counterweights 3E and 3? associated with or carried by the valve shaft 25 are larger or of greater mass for the type of valve shaft illustrated than the counterweights 33 and 39 and said counterweights 36, 3'! are positioned at a slightly different phase angle in order to counterbalance at the same time the unbalanced rotating forces induced by the masses of the ball portions on the valve shaft. Figs. 3 and 4 clearly show this relationship. The counterweights on the valve shaft are constructed to balance the unbalanced rotating forces produced by the weights on the balance shaft plus the forces induced by the masses of the ball portions on the valve shaft.

If desired, the balance shaft 35 may be provided with accessory driving instrumentalities such as the cam fill or gear 4|. These shafts 25 and 35 may be driven from the crankshaft 20 by any suitable mechanism, one type of driving means being herein illustrated and consisting of a belt or chain 42 engaging the elements or sprockets t3, and 45 respectively carried by the valve shaft 25, balance shaft 35 and crankshaft a suitable idler gear 46 being preferably employed in order to drive the balance shaft 35 in the opposite direction from the valve shaft 25.

With the construction herein illustrated it will be noted that I have provided an engine which may be operated very smoothly and efficiently with a minimum of objectionable vibration. rurthermore, I have provided an engine of improved operating characteristics by providing means associated with the layshaft or valve shaft for counteracting the unbalanced rocking couple set up in the engine by the reciprocating movement of the associated sleeves and sleeve actuating means in a manner which provides a construe-tion which will not unnecessarily lengthen the engine block and which can be readily assembled with the said layshaft with a minimum of time and labor.

The balancing of this rocking couple caused by the reciprocating forces has become of major importance with the advent of high speed engines. The construction developed by applicant has been largely responsible for the success of engines of the aforesaid type as the incorporation of these balancing devices has eliminated objectionable vibration caused by an unbalanced primary rocking couple.

It will be apparent to those skilled in the art to which my invention pertains that various modifications and changes may be made therein without departing from the spirit of my invention or from the scope of the appended claim.

What I claim as my invention is:

In an internal. combustion engine of the type having a plurality of cylinders substantially aligned longitudinally of the engine, sleeve valve means associated with said cylinders, means including a layshaft having crank portions and driven from the engine for operating said sleeve valve means axially of said cylinders whereby a rocking couple is produced in the engine longitudinally thereof, and means actuated in relation with said layshaft for producing an op posing rocking couple in the engine, said second means including a balancing shaft having coon-- terweights and rotated in the opposite direction from said layshaft, said layshaft having counterweights of relatively larger mass than the coun terweights carried by said balancing shaft and having a slightly different phase angle to counterbalance the rotating forces produced by said counterweighted balancing shaft and the unbalanced rotating forces produced by the layshaft crank portions.

ANDRE J. MEYER. 

